Stream restoration is a popular approach for managing nitrogen (N) in degraded, flashy urban streams. Here, we investigated the long-term effects of stream restoration involving floodplain reconnection on riparian and in-stream N transport and transformation in an urban stream in the Chesapeake Bay watershed. We examined relationships between hydrology, chemistry, and biology using a Before/After-Control/Impact (BACI) study design to determine how hydrologic flashiness, nitrate (NO3−) concentrations (mg/L), and N flux, both NO3−and total N (kg/yr), changed after the restoration and floodplain hydrologic reconnection to its stream channel. We examined two independent surface water and groundwater data sets (EPA and USGS) collected from 2002–2012 at our study sites in the Minebank Run watershed. Restoration was completed during 2004 and 2005. Afterward, the monthly hydrologic flashiness index, based on mean monthly discharge, decreased over time from 2002 and 2008. However, from 2008–2012 hydrologic flashiness returned to pre-restoration levels. Based on the EPA data set, NO3−concentration in groundwater and surface water was significantly less after restoration while the control site showed no change. DOC and NO3−were negatively related before and after restoration suggesting C limitation of N transformations. Long-term trends in surface water NO3−concentrations based on USGS surface water data showed downwardmore »
- Publication Date:
- NSF-PAR ID:
- 10247274
- Journal Name:
- Soil Systems
- Volume:
- 5
- Issue:
- 1
- Page Range or eLocation-ID:
- 15
- ISSN:
- 2571-8789
- Sponsoring Org:
- National Science Foundation
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